/**
 * Copyright (c) 2021 OceanBase
 * OceanBase CE is licensed under Mulan PubL v2.
 * You can use this software according to the terms and conditions of the Mulan PubL v2.
 * You may obtain a copy of Mulan PubL v2 at:
 *          http://license.coscl.org.cn/MulanPubL-2.0
 * THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OF ANY KIND,
 * EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT,
 * MERCHANTABILITY OR FIT FOR A PARTICULAR PURPOSE.
 * See the Mulan PubL v2 for more details.
 */

#ifndef _OB_SQL_EXPR_NVL_
#define _OB_SQL_EXPR_NVL_

#include "sql/engine/expr/ob_expr_operator.h"

namespace oceanbase {
namespace sql {
class ObExprNvlUtil {
  public:
  static int calc_result_type(
      ObExprResType& type, ObExprResType& type1, ObExprResType& type2, common::ObExprTypeCtx& type_ctx);
  static int calc_nvl_expr(const ObExpr& expr, ObEvalCtx& ctx, ObDatum& res_datum);
  // for nvl2()
  static int calc_nvl_expr2(const ObExpr& expr, ObEvalCtx& ctx, ObDatum& res_datum);
};

class ObExprNvl : public ObFuncExprOperator {
  public:
  explicit ObExprNvl(common::ObIAllocator& alloc);
  virtual ~ObExprNvl();

  virtual int calc_result_type2(
      ObExprResType& type, ObExprResType& type1, ObExprResType& type2, common::ObExprTypeCtx& type_ctx) const;
  virtual int calc_result2(
      common::ObObj& result, const common::ObObj& obj1, const common::ObObj& obj2, common::ObExprCtx& expr_ctx) const;

  virtual int cg_expr(ObExprCGCtx& expr_cg_ctx, const ObRawExpr& raw_expr, ObExpr& rt_expr) const override;

  private:
  // disallow copy
  ObExprNvl(const ObExprNvl& other);
  ObExprNvl& operator=(const ObExprNvl& other);

  protected:
  // data members
};

class ObExprOracleNvl : public ObFuncExprOperator {
  public:
  // ObExprNvl();
  explicit ObExprOracleNvl(common::ObIAllocator& alloc);
  virtual ~ObExprOracleNvl();

  virtual int calc_result_type2(
      ObExprResType& type, ObExprResType& type1, ObExprResType& type2, common::ObExprTypeCtx& type_ctx) const;

  static int calc_nvl_oralce_result_type(
      ObExprResType& type, ObExprResType& type1, ObExprResType& type2, common::ObExprTypeCtx& type_ctx);

  virtual int calc_result2(
      common::ObObj& result, const common::ObObj& obj1, const common::ObObj& obj2, common::ObExprCtx& expr_ctx) const;
  virtual int cg_expr(ObExprCGCtx& expr_cg_ctx, const ObRawExpr& raw_expr, ObExpr& rt_expr) const override;

  private:
  DISALLOW_COPY_AND_ASSIGN(ObExprOracleNvl);

  protected:
  // data members
};

class ObExprNaNvl : public ObFuncExprOperator {
  public:
  explicit ObExprNaNvl(common::ObIAllocator& alloc);
  virtual ~ObExprNaNvl();

  virtual int calc_result_type2(
      ObExprResType& type, ObExprResType& type1, ObExprResType& type2, common::ObExprTypeCtx& type_ctx) const;
  virtual int calc_result2(
      common::ObObj& result, const common::ObObj& obj1, const common::ObObj& obj2, common::ObExprCtx& expr_ctx) const;
  virtual int cg_expr(ObExprCGCtx& expr_cg_ctx, const ObRawExpr& raw_expr, ObExpr& rt_expr) const override;

  private:
  DISALLOW_COPY_AND_ASSIGN(ObExprNaNvl);

  protected:
  // data members
};

}  // namespace sql
}  // namespace oceanbase
#endif
